Answer:
there I think the answer is measuring tape we cannot use a metre rule because it measures straight lines and I think measuring tape is better because it is flexible thus makes measurement easier
this question is centered around newtons second law f=ma
First you need to find the acceleration

that gives you 0.36 recurring(on both numbers) m/s²
mass= force ÷ acceleration

mass= 85.25 kg
if you want to check
f=ma
85.25 × 0.36 recurring (remember its on both numbers not just 6) = 31 N
Answer:
a) 27.2 V
b)27.2 V
Explanation:
Charge of the electron =charge of the proton = q = 1.6 × 10⁻¹⁹ C
Radius = r = 0.53×10⁻¹⁰ m
Electric Potential = V = k q/r
k = 9 ×10⁹ N m²/C² = Coulomb's constant.
V = (9 ×10⁹)(1.6 × 10⁻¹⁹)/( 0.53×10⁻¹⁰) = 27.2 V
b) Potential Energy of the electron = k q × q / r
= [(9 ×10⁹)(1.6 × 10⁻¹⁹)(1.6 × 10⁻¹⁹) / (0.53×10⁻¹⁰)] / (1.6 × 10⁻¹⁹) eV,
since 1 electron volt = (1.6 × 10⁻¹⁹)joules
= 27.2 eV
Guardrail systems must be capable of withstanding at least 200 pounds of force applied within 2 inches of the top edge, in any direction and at any point along the edge, and without causing the top edge of the guardrail to deflect downward to a height less than 39 inches above the walking/working level.